1. Phylum: Chordata Vertebrates Fish and Amphibians

2. Vertebrate Characteristics To be in the phylum Chordata you must have these four characteristics at some point in your development To be in the phylum Chordata you must have these four characteristics at some point in your development 1. dorsal, hollow nerve cord (backbone) 1. dorsal, hollow nerve cord (backbone) 2. a notochord (most when embryos) 2. a notochord (most when embryos) 3. pharyngeal pouches (turn into gills) 3. pharyngeal pouches (turn into gills) 4. tail that extends beyond the anus 4. tail that extends beyond the anus

3. Fishes Fishes are aquatic vertebrates which have Fishes are aquatic vertebrates which have Paired fins - movement Paired fins - movement Scales – protection (can tell age of some fish by counting the rings) Scales – protection (can tell age of some fish by counting the rings) Gills – exchanging oxygen and carbon dioxide Gills – exchanging oxygen and carbon dioxide

4. Groups of Fish 1. Jawless Fish 1. Jawless Fish no teeth or jaws no teeth or jaws Keep notochord as adults Keep notochord as adults Many are parasites, no swim bladder Many are parasites, no swim bladder Examples – Examples –hagfishandlampreys

5. Groups of Fish 2. Cartilaginous Fish 2. Cartilaginous Fish Skeleton made of cartilage Skeleton made of cartilage Tooth-like scales covering skin Tooth-like scales covering skin 350 species – most are under 3 feet 350 species – most are under 3 feet Teeth are replaced when worn out – 20,000 in lifetime Teeth are replaced when worn out – 20,000 in lifetime Examples: sharks, rays, skates Examples: sharks, rays, skates

6. Groups of Fish 3. Bony Fish – called ray-finned fish 3. Bony Fish – called ray-finned fish Very diverse group Very diverse group Most have a swim bladder Most have a swim bladder Anadromous fish can move from salt to fresh water Anadromous fish can move from salt to fresh water

7. Amphibians  Amphibian means double life –water and land Larvae- use gills- live in water Larvae- use gills- live in water Adults – use lungs – live on land Adults – use lungs – live on land  Moist skin  No scales  No claws  Tympanic membrane behind eye (ear )

8. Surinam Frog After the female lays her pea-sized eggs, the male places them on her back and pushes them into her spongy skin. The eggs incubate as mom's new skin slowly develops and covers them, keeping them safe and out of sight. They then hatch out of her back. Life cycle of Frogs

9. Groups of Amphibians 1. Salamanders Long bodies and tails Long bodies and tails Four legs Four legs Carnivores Carnivores Live in moist woods Live in moist woods Some keep gills their entire lives Some keep gills their entire lives

10. Groups of Amphibians 2.Frogs and Toads Frogs – long legs for jumping and they are closely tied to water. Toads – short legs and often live in moist woods or even deserts.

11. Groups of Amphibians 3. Caecilians – legless animals that live in water or burrow in moist soil. Some feed on termites. Fish like scales in their skin. 3. Caecilians – legless animals that live in water or burrow in moist soil. Some feed on termites. Fish like scales in their skin.